The wrist joint comprises a number of articulations between a) the radius and ulna and the carpal bones of the wrist, b) the articulations between the carpal bones themselves, and c) the articulations between the carpal bones may be characterized as having a proximal row of bones (scaphoid, lunate, triquetrum, and pisiform) and a distal row of bones (trapezium, trapezoid, capitate, and hamate). Two sets of ligaments are also found: 1) an intrinsic or interosseous set of ligaments which connect the carpals directly, and 2) an extrinsic set of ligaments which are thickened portions of the wrist capsule. The wrist capsule is a firm fibrous layer surrounding the entire wrist, which has some areas of fibrous thickening which constitute the extrinsic dorsal and volar ligaments.
Acute injuries to the wrist ligaments may result from forward or backward falls onto an outstretched hand, as well as torsion or twisting injuries from outdoor sports and activities, and may be associated with fractures of the distal radius or carpal fractures. One of the most common injuries from such falls is a tear of the scapho-lunate (“S-L”) ligament. Other ligaments, such as the Luno-Triquetral ligament can also tear and require repair.